Activity 3.11 Class 10 Science

In this activity, we will discuss the chemical reaction between different metals with acid and compare the reactivity of different metals.

Reactivity of Metals with Dilute Hydrochloric Acid

Aim of the activity

To study the reactions of metals with acid

Materials Required

    1. Matal samples (Ca, Mg, Al, Zn, Fe, Cu)

    2. Dilute HCl

    3. Test tubes

    4. Sandpaper

    5. Thermometers

    6. Test tube stand

    7. Safety goggles & gloves

Procedure

We clean all metal samples with sandpaper to remove any oxide coating and place each sample in separate test tubes. Now we add a few drops of dilute hydrochloric acid. We insert a thermometer into each test tube and measure temperature change. We also observe formation of gas bubbles.

 

Observation

Metal	Rate of bubble formation	Temperature	Reactivity
Ca	Very fast	High	Very reactive
Mg	Fast	High	Highly reactive
Al	Moderate	Moderate	Reactive
Zn	Moderate	Moderate	Reactive
Fe	Slow	Low	Less reactive
Cu	No bubbles	No change	Not reactive

 

Explanation

Metals react with acid to form salt and release hydrogen gas. The rate of reaction is different with different metals.

 

Metal + Acid →Salt +Hydrogen gas

 

Mg + 2HCl →MgCl₂ +H₂

2Al + 6HCl→ 2AlCl₃ + 3H₂

Zn + 2HCl→ZnCl₂ + H₂

Order of Reactivity

Ca >Mg> Al> Zn> Fe> Cu

Calcium is the most reactive and copper is less reactive in this series.

Conclusion

We can conclude the reactivity of metals with dilute acid in this activity.

Frequently Asked Questions

    1. Why are sodium and potassium not used in this activity?

Answer – Because they react vigorously and can cause explosion.

   2. What gas is evolved when metals react with acid?

Answer – Hydrogen gas

   3. Which metal does not react with hydrochloric acid?

Answer- Copper

   4.  Why doesn’t copper react with dilute HCl?

Answer – Because copper is less reactive than hydrogen.